What is a radar sensor?

Whether you realize it or not, we use radar sensors every day for different applications. Radar sensors are used for the weekly weather forecast, traffic control, and onboard vehicle systems. In recent years, they have been used for wearable devices, smart buildings, and autonomous cars. But what exactly is a radar sensor?

Radar sensors are conversion devices that transform microwave echo signals into electrical signals. They use wireless sensing technology to detect motion by figuring out the object’s position, shape, motion characteristics, and motion trajectory. Unlike other sensors, radar sensors aren’t affected by light and darkness and with the ability to detect obstructions like glass, it can “see” through walls. When compared to other sensor technology, like ultrasound, radar can sense longer distances and is safe for people and animals.

One of the biggest advantages radar sensors have over other sensors is its detection of motion and velocity. By detecting an object’s Doppler effect, or change in wave frequency, a radar sensor can compute that object’s speed along with its direction. They can also observe the target’s movement from different perspectives when using multi-channel sensors. Examining the movement from different perspectives in addition to previously collected measurements are used to determine complex movements.  

This radar technology is found in various systems but is most prominently used in CW Doppler and FMCW radar sensors. Doppler radars are specialized radars that use the Doppler effect to measure a target’s speed at different distances. And FMCW radar sensors are used to measure a target’s distance. Unlike the Doppler Radar, the FMCW changes its frequency over time according to the law of triangle waves.

So now that we know how radar sensors, how are they used? We went over some examples earlier, but the truth is, radar sensor technology is used in lots of different applications from military operations such as missile guidance and medical devices, even traffic control. The chart below outlines some of the key uses.

Radar sensor applications table

There’s no doubt about the importance of radar sensors. Without it, we wouldn’t be able to predict the weather, track temperature changes, or drive our smart cars. As the market continues to grow, recent reports predict radar sensors to see a huge growth by 2027, the technology is sure to continue to improve and be applied in innovative ways.

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